It's probably a problem with your network. One way this can happen is if users switch networks, such as from a wired to a wireless connection or from an internal to an external connection, where it ends up connecting to a different CAS that doesn't
know about its existing connection. For example, say you have a wired netowrk that goes straight to the CAS, and you have a wireless network that goes through a TMG server that load balances a server farm of CAS servers. When you unplug your wired
connection, the connection switches paths, and an authentication dialog pops up because the new CAS to which you're connection knows nothing about your session.
This can also happen if you have misconfigured load balancers, CAS servers using DNS round-robin "load balancing" (which isn't), or any number of other network issues.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."
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